Monday, August 5, 2013

Geography of Algeria

Algeria comprises 2,381,741 square kilometers of land, more than four-fifths of which is desert, in northern Africa, between Morocco and Tunisia. It is the largest country in Africa. Its Arabic name, Al Jazair (the islands), derives from the name of the capital Algiers (Al Jazair in Arabic), after the small islands formerly found in its harbor. It has a long Mediterranean coastline, most of which is more properly termed the Alboran Sea, which is the westernmost element of the Mediterranean Sea. The northern portion, an area of mountains, valleys, and plateaus between the Med.

iterranean Sea and theSahara Desert, forms an integral part of the section of North Africa known as the Maghreb. This area includes Morocco, Tunisia, and the northwestern portion of Libya known historically as Tripolitania.

Tell Atlas, High Plateaus and the Saharan Atlas

Stretching from the Moroccan border the Tell Atlas, including the Djebel Babor formation, is
the dominant northwestern mountain range. Stretching more than 600 kilometers
eastward from the Moroccan border, the High
Plateaus (often referred to by their French name Hauts Plateaux) consist
of undulating, steppe-like plains lying between the Tell and Saharan Atlas ranges. The
plateaus average between 1,100 and 1,300 meters in elevation in the west,
dropping to 400 meters in the east. So dry that they are sometimes thought of as
part of the Sahara, the plateaus are covered by alluvial debris formed when the
mountains eroded. An occasional ridge projects through the alluvial cover to
interrupt the monotony of the landscape.

Higher and more continuous than the Tell Atlas, the Sahara Atlas range is
formed of three massifs: the Ksour Range near the Moroccan border, the Amour Range, and the Ouled-Naïl
Range south of Algiers. The
mountains, which receive more rainfall than those of the High Plateaus, include
some good grazing land. Watercourses on the southern slopes of these massifs
disappear into the desert but supply the wells of numerous oases along the
northern edge of the desert, of which Biskra, Laghouat, and Béchar are the most prominent.

Northeastern
Algeria

Eastern Algeria consists of a massive area extensively dissected into
mountains, plains, and basins. It differs from the western portion of the
country in that its prominent topographic features do not parallel the coast. In
its southern sector, the steep cliffs and long ridges of the Aurès Mountains
create an almost impenetrable refuge that has played an important part in the
history of the Maghrib since Roman times. Near the northern coast, the Petite
Kabylie Mountains are separated from the Grande Kabylie range at the
eastward limits of the Tell by the Soummam River. The coast is predominantly
mountainous in the far eastern part of the country, but limited plains provide
hinterlands for the port cities of Bejaïa, Skikda, and Annaba. In the interior
of the region, extensive high plains mark the region around Sétif and Constantine; these plains were developed
during the French colonial period as the principal centers of grain cultivation.
Near Constantine, salt marshes offer seasonal grazing grounds to seminomadic
sheep herders.The Sahara
The Algerian portion of the Sahara extends south of the Saharan Atlas for
1,500 kilometers to the Niger and Mali frontiers. The desert is an otherworldly
place, scarcely considered an integral part of the country. Far from being
covered wholly by sweeps of sand, however, it is a region of great diversity.
Immense areas of sand dunes called areg (sing., erg) occupy about one-quarter of
the territory. The largest such region is the Grand Erg Oriental (Great Eastern Erg),
where enormous dunes two to five meters high are spaced about 40 meters apart.
Much of the remainder of the desert is covered by rocky platforms called humud
(sing., hamada), and almost the entire southeastern quarter is taken up by the
high, complex mass of the Ahaggar and Tassili n'Ajjer highlands, some parts of
which reach more than 2,000 meters. Surrounding the Ahaggar are sandstone
plateaus, cut into deep gorges by ancient rivers, and to the west a desert of
pebbles stretches to the Mali frontier.

The desert consists of readily distinguishable northern and southern sectors,
the northern sector extending southward a little less than half the distance to
the Niger and Mali frontiers. The north, less arid than the south,
supports most of the few persons who live in the region and contains most of the
desert's oases. Sand dunes are the most prominent features of this area's
topography, but between the desert areas of the Grand Erg Oriental and the Grand Erg
Occidental (Great Western Erg) and extending north to the Atlas Saharien are
plateaus, including a complex limestone structure called the M'zab where the M'zabiteBerbers have settled. The southern zone of the
Sahara is almost totally arid and is inhabited only by the Tuareg nomads and,
recently, by oil camp workers. Barren rock predominates, but in some parts of
Ahaggar and Tassili n'Ajjer alluvial deposits permit garden farming.